Physical activity is an important factor in maintaining good overall health and wellbeing. Being physically active has significant health benefits, including reducing the risk of some chronic conditions, helping to control weight, and improving mental wellbeing [1]. Some forms of physical activity may also help manage long-term conditions, such as arthritis and Type 2 diabetes, by reducing their effects and improving quality of life.

In recent decades, there has been a decline in physical activity due to the increasing sedentary nature of many forms of work and activities such as watching television or using a computer, as well as changes in transportation [2]. Sedentary behaviour is believed to be associated with the rise in overweight and obesity, and has been shown to increase an individual's risk of cardiovascular disease, colon and breast cancers, Type 2 diabetes and osteoporosis [3]. A recent study estimated that the direct health care costs due to physical inactivity in Australia were almost $1.5 billion in 2006-07, the largest of which were attributable to falls ($469 million) and coronary heart disease ($372 million) [4].

Worldwide, physical inactivity is the fourth leading risk factor for global mortality, contributing to 6% of deaths [5], and is second only to tobacco smoking as a leading modifiable health risk factor contributing to the burden of disease and injury in Australia. It is the fifth leading risk factor for men and the third leading risk factor for women [6].

This article provides an overview of the physical activity levels of adults in Australia, including information on a range of factors which may influence these levels and the long-term health risks associated with physical inactivity.